package org.util.mqttclient;

import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import org.eclipse.paho.client.mqttv3.MqttCallback;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttConnectOptions;
import org.eclipse.paho.client.mqttv3.MqttMessage;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;

public class MqttTopicListener {
	private MqttClient client;
	private String host;
	private String userName ;
	private String passWord ;
	private String topicName;
	private String deviceId;
	private ReceivedCallback receivedCallback;
	
	private MqttConnectOptions options;
	
	public MqttTopicListener(String host,String username,String password,String topicName,String deviceId){
		this.host = host;
		this.userName = username;
		this.passWord = password;
		this.topicName = topicName;
		this.deviceId = deviceId;
	}
	
	public void start(ReceivedCallback receivedCallback){
		this.receivedCallback = receivedCallback;
		init();
	}
	
	private void init() {
		try {
                       //host为主机名，test为clientid即连接MQTT的客户端ID，一般以客户端唯一标识符表示，MemoryPersistence设置clientid的保存形式，默认为以内存保存
			client = new MqttClient(host, deviceId,
					new MemoryPersistence());
                       //MQTT的连接设置
			options = new MqttConnectOptions();
                       //设置是否清空session,这里如果设置为false表示服务器会保留客户端的连接记录，这里设置为true表示每次连接到服务器都以新的身份连接
			options.setCleanSession(true);
                       //设置连接的用户名
			options.setUserName(userName);
                       //设置连接的密码
			options.setPassword(passWord.toCharArray());
			// 设置超时时间 单位为秒
			options.setConnectionTimeout(10);
			// 设置会话心跳时间 单位为秒 服务器会每隔1.5*20秒的时间向客户端发送个消息判断客户端是否在线，但这个方法并没有重连的机制
			options.setKeepAliveInterval(20);
                        //设置回调
			client.setCallback(new MqttCallback() {

				@Override
				public void connectionLost(Throwable cause) {
                                        //连接丢失后，一般在这里面进行重连
					System.out.println("connectionLost----------");
					
				}

				@Override
				public void deliveryComplete(IMqttDeliveryToken token) {
                                        //publish后会执行到这里
					System.out.println("deliveryComplete---------"
							+ token.isComplete());
				}

				@Override
				public void messageArrived(String topicName, MqttMessage message)
						throws Exception {
                                        //subscribe后得到的消息会执行到这里面
					receivedCallback.receivedHandler(message.toString());
					System.out.println(topicName+":"+message);
					System.out.println("messageArrived----------");
				}
			});
			client.connect(options);
			client.subscribe(topicName, 1);
//			connect();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}
